[Trunkcom] 400mhz trunking system help needed

[Brian J Cathcart]

On Mon, 31 Dec 2001 22:53:15 -0600 sly.debbie@verizon.net writes:
> I have ran Trunker for a while on the control channel (it is an 
> astrosystem). As you know trunker loads the freqs in the hex value for 
> the channel #. So far I've  got values from 109(06d)  to 749(2ed).

Hex 000 to 17B are input frequencies, Hex 17C to 2F7 are outputs (and the
ones you want for the 780xlt). 


> I have been able to figure out a spacing of 12.5kc but thats it.

Yes, most Astro systems in this band use this spacing.


> I understand that the offset channel range is from 380-759. So 
> whats up with the 109 channel # and some others I have below 380?

Input frequencies.  UHF and VHF Motorola systems transmit both the output
and input hex values on the control channel.  While running Trunker you
will see each output hex value "light up", and at the same time the input
value will "light up" with it.  For using the 780xlt, you only need to
woory about the hex values from 17C to 2F7.


> Also whats the purpose of 3 different base configs for the 
> system?

VHF and UHF systems have the ability to specify 3 sets of Base and
Offsets to give them flexibilty in the frequency layout.  The 780xlt is
able to track systems like this.


> Anyway if someone could help me out in general for programming 
> 400mhz systems I'd appreciate it or point me to a url with the info on 
> it.

Since you are running Trunker you are way ahead of the game.  The easiest
thing to do at this point is download my Base&Offset Excel spreadsheet
from the files section of the Trunker mailing list
(http://groups.yahoo.com/group/trunker/; you will have to be a subscriber
to the Trunker list, something easy to do).  In it you plug in the hex
values, offset, and one of the system frequencies and it will give you
all of the remaining frequency hex values.

--

The Scanner Dude
Brian J. Cathcart - KE4PMJ
South Florida Trunking Guide - 5th Edition (On CD-ROM too!)
Palm Beach County Frequency Directory - 4th Edition (On CD-ROM too!)